Posted by **harry** on Sunday, November 5, 2006 at 4:04pm.

A rocket weighs 1 x10^7 N while on the surface of the earth. The ignition of its engines results in a lift off force of 1.5 X 10^7 N

a) what is the mass of the rocket.

b) what is its acceleration at lift -off

c)How fast will it be moving if it acceleartion at this rates for 10 minutes.

d) How high will it be after 10 minutes.

1 the weight is mg, solve for m

2 Lift off force=mg + ma solve for a

vf=at change t to seconds

h=1/2 a t^2

The reality is that the weight of the rocket decreases as fuel is burned. I suppose your teacher wants to ignore that.

Thank you Mr Bob Pursley